1. Field of the Invention
The present invention relates generally to the field of accessories for computerized simulation programs and more specifically to a device which simulates the major controls of an airplane for use with computerized flight simulation programs, and which utilizes the user's existing computer joysticks.
2. Description of the Prior Art
Within the last several years numerous flight simulation computer programs have appeared on the market and have enjoyed great popularity. An example is "Flight Simulator," sold by the Microsoft Corporation of Redmond, Wash., which has been popular with the general public for entertainment use and also with individuals who are or who intend to be enrolled in a formal flight training course. Until recently the only devices available, other than the computer keyboard itself, to operate certain flight controls in such simulation programs were small computer joysticks.
There are several problems with such use of joysticks. First, the short throw of the joystick lever can result in overcontrol of the ailerons, elevator, rudder, and throttle in the simulation, since the two to four inch total movement of the joystick lever is roughly only one fifth of the corresponding movement of the stick in a real airplane. Secondly, the resistive forces provided by the self-centering springs of the joysticks are a small fraction of the corresponding control forces of the stick and rudder pedals in a real airplane. Thirdly, in the instance of the rudder, the hand control offered by the joystick does not adequately represent the foot pedal control of the rudder in a real airplane. Fourthly, in typical joystick usage the arrangement of the joystick(s) with respect to the user does not reflect the arrangement of the corresponding stick, rudder, and throttle controls with respect to the pilot of a real airplane.
Recently, several devices have been developed to eliminate some of the above problems. Examples are the MAXX Control Yoke manufactured by the Alturas Corporation, of Coeur d'Arlene, Id., and a "Flight Simulation Control Apparatus," U.S. Pat. No. 4,887,966, each of which offers a full size rendition of a modern aircraft wheel type control yoke, provides more realistic resistive forces for ailerons and elevator, and offers a throttle control. These devices are clamped to or positioned atop a computer table or stand in front of the user in a position relative to him or her which represents the position of the control yoke relative to the pilot of a real airplane, and the devices are then connected to the computer through an umbilical cord. Another example is the "Aircraft Controls Simulator," U.S. Pat. No. 4,713,007, in which a cabinet containing a full size control yoke and throttle is placed on the computer table and a second cabinet containing rudder pedals is placed on the floor in an arrangement akin to the control yoke and rudder pedals in a real airplane. Common to these devices is that they incorporate electromechanical componentry which in essence duplicate the function of the electromechanical componentry of conventional joysticks, more specifically that of sensing and electronically transmitting the position of the user-manipulated elements.
A similar series of devices offers full size controls like the above but is designed to function in conjunction with commercially available joysticks. One such device, termed a "Joystick Control Accessory for Computerized Aircraft Flight Simulator Program," U.S. Pat. No. 4,820,162, is an accessory employing a joystick extension tube connected to four springs to produce realistic sensations of control movement resistance. In this accessory the extension tube is mounted directly onto the computer joystick via the small screws in the latter's dome-shaped cap which is removed for the installation, while the joystick housing is immobilized by brackets on the accessory's base. However, the extension appears to be adapted to a particular configuration of joystick rather than many, and provides for a semi-permanent installation thus not facilitating the use of the installed joystick for other purposes. Another device of this type is a "Control Yoke Apparatus for Computerized Aircraft Simulation," U.S. Pat. No. 4,659,313, in which a cabinet containing a control yoke connected to a computer joystick is placed on the computer table. It appears that the joystick is semi-permanently installed in the device and that modification to the joystick may be required for the installation, and thus as in the previous example the installed joystick appears not readily available for other uses.
Another type of device, termed a "Transmitter Extension Apparatus for Manipulating Model Vehicles," U.S. Pat. No. 4,386,914, for use in the general area of radio controlled aircraft, offers full size controls including joystick, throttle, and rudder pedals which are connected to and actuate small joysticks on a separate commercially available radio transmitter. However, this device requires a relatively large platform type base and a built-in dedicated seat. Devices of this type for a computer flight simulation application would be cumbersome to remove from the work station when the user desired to use the computer for another application, and would likely present difficulties in the seated user's access to the keyboard and viewing of the computer monitor.
Many individuals have purchased joysticks for use in various computer programs and games, including flight simulation programs. These joysticks continue to become more sophisticated and expensive such that a pair of the top-of-the-line models may represent a substantial investment in computer game peripheral equipment. Available accessories such as the examples described above do provide relief from one or more of the problems in using joysticks in flight simulation programs. However, as shown above, none of these accessories or devices has the combined attributes of providing full-size controls representing the stick, rudder pedals, and throttle, while utilizing the electronics in the user's existing joysticks, and performing these functions in such a way that minimizes interference with use of these joysticks and/or computer in other applications. The buyer of these devices either must incur an additional expense in paying for duplication of the electromechanical componentry furnished in his existing joysticks (plus lose the opportunity to utilize the excellent operational characteristics of the more expensive joysticks in cases where the user owns such), or must accept the restriction of his existing joystick(s) being relatively unavailable for other applications once installed in the flight simulation device, or must be content with partial primary flight controls (no rudder pedals), or must accept (with a platform type device) that the device will intrude upon the utility of the work station and general work area because of the device's size and will allow less than optimum access to the monitor and keyboard during use, or must accept combinations of such limitations.